Stamp pad



June 24, 1947-' c. F. ALEXANDER l STAMP PAD 2 Sheets-Sheet l Filed Dec. 22, 1945 Jue 24, 1947. v c. F. ALEXANDER STAMP PAD Filed Dec. 22, -1945 2 Sheets-Sheet 2 INVENTR. Carles Zexa/zz/def Patented .une 24, 1947 UNITED. STATES. PATENT' OFFICE Charles F. Alexander, Chicago, Ill.

. Application December 22, 1945, Serial No. 637,028

",Thisinvention relates tostarn-p pads or liquid retaining and dispensing devices and particularly to the type of pads that are used as ink pads for inking hand stamps or rubber stamps and the like.

,In stamp pads and ink pads as heretofore constructed, therehas always been the danger that thevink or other liquid contained within the pad will evaporate and cause the pad to become sticky and difficultY to use, and an important object oi the present invention is to eliminate this dii- `nculty in stamp pads of the aforesaid character. It has been customary in the past to form stamp pads of the kind to which this invention relates f romidiierent kinds of materials, and among the materials that have thus been used are spo-nge rubber pads that are mounted in a suitable holder or carrier and which vretain the ink in a relatively satisfactory manner. Such ink pads as heretofore constructed from sponge rub-ber have had the objectionable characteristics that the amount of ink that could be held in such pads was relatively limited, and attempts have been made to increase the inkcarrying capacity of such pads through the provision of what have been termed reservoirs or wells formed within the body of the sponge rubber that constitutes the pad. Such an arrangement however makes it relatively diiiicult to replenish the ink supply in such ink pads, and it is therefore a further object of the presentA invention to simplify the construction of such ink pads and to enable a supply of ink to be afforded in such ink pads in a way that simplies the replenishing of such ink supply. More speciiicallyl it is an object of the present invention to so construct the ink pad that a relatively great supply of ink is incorporated in the ink pad assembly and to protect such ink against evaporation while enabling the ink to be applied to the sponge rubber of the pad in a` relativelysimple manner.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show a preferred embodiment and the principle thereof and what I now consider to be the best mode in which I have contemplated applying that principle. Other embodiments of the invention embodyingthe same or equivalent principle may 4be used and structuralchanges may be made as desired by those skilled in the art without departing from the present invention and the purview of the appendedy claims. p

In the drawings,

Fig. 1 is a vplan view of an ink pad embodying the features of the invention; Fig. Zisan endview of the ink pad shown in 11 Claims. (Cl. 91-545) Fig. ,3 is a plan view of the mounting base of 'the ink pad with the pad member removed;

Fig. 4 is a transverse sectional view taken substantially along the line 4-4 of Fig. 1;

Fig. 5 is a sectional view taken along the line 5-5 of Fig. 3;

Fig. 6 is a sectional view taken substantially along the line 6-6 of Fig. 1;

Fig. 'l is an enlarged cross sectional view of a portion of the sponge rubber pad;

Fig. 8 is a iragmental View showing the sponge rubber pad in the form that it assumes when the pad is stretched in a right to left direction as shownin this view;

Fig. 9 is an enlarged cross sectional view showing the 'form that the ink receiving member takes in the course of `a filling or ink replenishing operation; i

Fig. `1I) is a fragmental plan view of the structure shown in Fig. 9; and

Fig; V11 is an enlarged portion of Fig. 9.

YIn the form chosen for disclosure herein the invention is embodied in a relatively small ink pad I5 of the kind that is adapted for use in a busiside `walls II that dene'a mounting pocket I8 which is in the present instance generally rectangular inform as will be evident in Figs. 3 and 5. The side walls I1 are rabbeted at I'IA about `their upper outer edges so as to be adapted to receive a conventional cover that is well known in the art. The base I6 may be made from any preferred material such as hard rubber, but for purposes of clarity in the present disclosure, and to avoid confusion with the sectioning applied to i another element of the device, the sectional views of the base Ihave not been cross sectioned as hard rubber..

The rectangular recess I8 is adapted to receive a pad member 20 that is made from sponge rubber, and in practice, the pad 20 is made of such a vsize that it substantially iills the recess 20 and is in rm abutment with the side walls I'I. The edges 4of the pad 20 are secured to the walls II by an adhesivejoint 20A, Fig. 9, so that this connection between the side edges of the pad 20 and the walls I'I will serve to prevent movement of ink or other liquid upwardly about the side edges ofthe pad 2B.

The base I6 is so formed that the recess I8 has a nat bottom wall or surface 22, and this bottom wall serves to. support the pad 20 which rests upon this bottom Wall- 22. The bottom wall or surface 20, however, is in accordance with the present invention so formed as to afford a plurality lof ink reservoirs 24 that are relatively wide and shallow so that ink may be stored inthe reservoir 24 and beneath the lower face of the pad 20. VThe reservoirs 24 are connected by channels 25 so that ink maybe caused to run from one reservoir to another, thereby to secure relatively even distribution of the ink supply within the various reservoirs 24.

The pad is in the present case formed from commercially available sponge rubber'that is furnished in relatively thick sheets, and such sheets are known to have a water-tight or liquid-tight skin 3l), Fig. 11, on the outer` faces of the block of sponge rubber, and in forming the pad 20 of the present device, such a block of sponge rubber is split longitudinally and substantially midway between the opposite faces that are covered by the skin 30. Then, in mounting the pad 20 in the base i6, the pad is placed in position in the recess I8 with the skin 3U disposed in abutment with the at bottom wall 22 of the recess I8. Thus when the pad 20 is secured in position in the recess i8 by the water-tight adhesive joint 20A, the reservoirs 24 will in effect be sealed against the entrance of air, and this characteristic is utilized under the present invention in attaining a highly advantageous mode of operation that renders thepresent ink pad more useful than the prior ink pads having sponge rubber as the ink retaining means. Thus as will be evident in Figs. 1, 4, and 6 to 10, the pad 20 has a plurality of slits 35 formed therein, such slits preferably being arranged in rows extending longitudinally and transversely of the pad 20, and these slits are of such a character that the normal action of the pad 2U maintains these slits 35 closed at all times except when a distorting force or pressure is applied to the pad. 'Ihe arrangement of the slits 35 is such that at least one such slit is disposed over each reservoir 24. Thus when the pad is pressed downwardly by the users hand or by means such as a Stamp S, one or more of the slits 35 will open at their lower ends, thereby to allow ink to move in the opened slit and thereby freely enter into the spaces or passages that are normally afforded in Sponges of this character. The slits 35 thus tend to produce uniform ink distribution throughout the area of the pad 20, and these slits also enable the ink supply in the reservoirs 24 to be readily replenished, as Well as enabling the ink from such reservoirs 24 to be transferred into the body of the bed 23 when this is necessary to replenish the ink supply within the body of the pad. Thus, as will be evident in Figs. 9 and 1l of the drawings, the pad 20 may be pressed downwardly by.

any convenient means such as an end edge of the stamp S, and when this is done, the lower ends of at least certain of the slits 35 will be opened as shown at 35A in Figs. 9 and 11. This same distortion of the portion of the pad 20 will move the open end 35A of the slit down into the body of ink that is Within the chamber 24. Thus the ink within the chamber 24 will flow into the open end 35A of the slit 35 and into the normal spaces of the sponge. The downward pressure on the stamp S may then be removed so that the body of the sponge will resume its normal form as shown in Fig. 4, and when such normal form has been attained, the lower end of the slit 25 will have been closed so as to thereby render the skin in effect continuous over the top of the reservoir 24. 'I'hus the ink within the reservoir 24 is again sealed against the entrance of air and 'will be retained in this reservoir in its proper condition pending the need for replenishing of the ink supply in the body of the pad 20.

When the entire ink supply in the reservoir 24 has been used or transferred into the body of the pad in the manner just described, the ink supply in the reservoir 24 may readily be replen ished merely by passing the end of a medicine or ink dropper downwardly through one of the slits 35 so that ink from the dropper may be discharged directly into they reservoir 24. The ink that is thus discharged into a particular one of the reservoirs 24 will of course tend to now into the other reservoirs through the interconnecting channels 25, but of course the user may insert the ink dropper through different ones of the slits 35 so as to discharge the ink into different ones of the reservoirs 24.

It Will be observed of course that the reservoirs 24 are separated by what might be termed ridges 24A, and it is through the ridges 24A that the channels 25 are formed, and these ridges 24A serve to support the ink pad 2B so as to insure proper contact of the pad with a stamp as S when such a stamp is applied to the ink pad in the normal or customary manner.

From the foregoing disclosure it will be apparent that the present invention affords an ink pad that is simple in character and which enables a supply of ink to be stored in association with the pad without danger of evaporation of such ink. The arrangement under the present invention is such that ink or other liquid may be readily transferred from the reservoirs to the body of the pad and this may be accomplished in a manner that may be readily performed by the persons who ordinarily use ink pads of the kind t0 which this invention relates.

I claim:

l. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall defining a recess having a generally flat bottom surface, said bottom wall having a plurality of spaced reservoirs formed therein as depressions opening through said flat bottom surface, said bottom wall having channels formed therein connecting said reservoirs so as to permit flow of liquid between such connected reservoirs, a pad member formed from sponge rubber and having a liquid tight skin on one flat face thereof, said pad member being disposed in said recess with said liquid tight skin resting on said flat bottom surface of said recess, adhesive means securing edge portions of said pad member to said wall to form a liquid-tight seal with said wall about said edges, said pad member having a plurality of spaced self-closing slits extended therethrough and positioned so that at least one such slit is disposed over each of said reservoirs.

2. In a stamp pad, a base formed to aiford an upstanding Wall and a bottom wall defining a recess having a generally fiat bottom surface, said bottom wall having a plurality of spaced reservoirs formed therein as depressions opening through said nat bottom surface, a pad member formed from sponge rubber and having a liquid tight skin on one flat face thereof, said pad member being disposed in said recess with said liquid tight skin resting on said flat bottom surface of said recess, adhesive means securing edge portions of said pad member to said wall to form a liquid-tight seal with said wall about said edges, said pad member having a plurality of spaced self-closing slits extended therethrough and positioned so that at least one such slit is disposed over each of said reservoirs.

3. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall defining a recess liaving a generally flat bottom surface, Said bottom wall having a plurality of spaced reservoirs formed therein as depressions opening through said iiat bottom surface, said bottom wall having channels formed therein connecting said reservoirs so as to permit iiow of liquid between such connected reservoirs, a pad member formed from sponge rubber and having a liquid tight skin on one flat face thereof, said pad member being disposed in said recess with said liquid tight skin resting on said flat bottom surface of said recess, means forming a liquid tight seal between edge portions of said pad member and said recess, said pad member having a plurality of spaced self-closing slits extended therethrough and positioned so that at least one such slit is disposed over each of said reservoirs.

li. In a stamp pad, a base formed to afford an opstanding wall and a bottom wall defining a recess having a generally at bottom surface, said bottom wall having a plurality of spaced reservoirs formed therein as depressions opening through said flat bottom surface, a pad member formed from sponge rubber and having a liquid tight skin on one flat face thereof, said pad member being disposed in said recess with said liquid tight skin resting on said flat bottom surface of said recess, means forming a liquid tight seal between edge portions of said pad member and said recess, said pad member having a plurality of spaced self-closing slits extended therethrough and positioned so that at 1east one such slit is disposed over each of said reservoirs.

5. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall defining a recess having a generally iiat bottom surface, said bottom wall having a plurality of spaced reservoirs formed therein as depressions opening through said flat bottom surface, said bottom wall having channels formed therein connecting said reservoirs so as to permit iiow of liquid between such connected reservoirs, a porous pad member disposed in said recess, a normally liquid tight resilient skin member disposed on said at bottom surface so as to overlie said reservoirs and sealed to the surfaces of said recess about the edges of said skin member, said skin member having a plurality of self-closing slits formed therein so as to dispose at least one such slit over each of said reservoirs.

6. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall defining a recess having a generally flat bottom surface, said bottom wall having a plurality of spaced reservoirs formed therein as depressions opening through said flat bottom surface, a pad member formed from sponge rubber and disposed in said recess so as to contact said walls about the edges of the recess, a normally liquid tight resilient skin member disposed on said flat bottom surface so as to overlie said reservoirs and sealed to the surfaces of said recess about the edges of said skin member, said skin member having a plurality of self-closing slits formed therein so as to dispose at least one such slit over each of said reservoirs.

7. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall defining a recess having a generally flat bottom surface, said bottom Wall having a plurality of spaced reservoirs formed therein as depressions opening through said iiat bottom surface, a pad member formed from sponge rubber and disposed in said recess so as to contact said walls about the edges of the recess, a normally liquid tight resilient skin member disposed on said flat bottom surface so as to'overlie said reservoirs and sealed to the surfaces of said recess about the edges of said skin member, said pad member and said skin member having a plurality of aligned selfclosing slits formed therein so as to dispose at least one such slit over each of Said reservoirs.

8, In a stamp pad, a base formed to afford an upstanding Wall and a bottom wall deningra recess having a generally nat bottom surface, said bottom wall having at least one depression formed therein and affording a reservoir opening through said flat bottom surface, a pad member formed from sponge rubber and having a liquid tight skin on one at face thereof, said pad member being disposed in said recess with said liquid tight skin resting on said flat bottom surface of said recessi adhesive means securing edge portions of said pad member to said Wall to form a liquid tight seal with said wall about said edges, said pad member having at least one self-closing slit extended therethrough and positioned so as to be disposed over said reservoir.

9. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall dening a recess having a generally flat bottom surface, said bottom wall having at least one depression formed therein and aifordinga reservoir opening through said flat bottom surface, a porous pad member disposed in said recess, a normally liquid tight resilient skin member disposed on said flat bottom surface so as to overlie said reservoir and sealed to the surfaces of said recess about the edges of said skin member, said skin member having at least one self-closing slit formed therein so as to be disposed over said reservoir.

10. In a stamp pad, a base formed to afford an upstanding wall and a .bottom wall dening a recess having a generally lat bottom surface, said bottom wall having at 1east one reservoir formed therein as a depression opening through said flat bottom surface, a pad member formed from sponge rubber and disposed in said recess so as to contact said walls about the edges of the recess, a normally liquid tight resilient skin member disposed on said flat bottom surface so as to overlie said reservoir and sealed to the surfaces of said recess about the edges of said skin member, said pad member and said skin member having at least one pair of aligned self-closing slits formed therein so as to be disposed over said reservoir.

11. In a stamp pad, a base formed to afford an upstanding wall and a bottom wall dening a recess having a generally flat bottom surface, said bottom wall having at least one reservoir formed therein as a depression opening through said iiat bottom surface, a pad member formed from sponge rubber and disposed in said recess so as to contact said walls about the edges of the recess, a normally liquid tight resilient skin member disposed on said fiat bottom surface so as to overlie said reservoir and sealed to the surfaces of said recess about the edges of said skin member, said skin member having at least one self-closing slit formed therein so as to be disposed over said reservo-ir.

CHARLES F. ALEXANDER.

REFERENCES CITED The following references are of record in the le of this patent:

Harris Apr. 24, 1945 

